package com.wei.youvie.service.impl;

import cn.hutool.core.collection.CollUtil;
import cn.hutool.core.util.StrUtil;
import com.baomidou.mybatisplus.core.conditions.query.QueryWrapper;
import com.baomidou.mybatisplus.extension.service.impl.ServiceImpl;
import com.wei.youvie.exception.BusinessException;
import com.wei.youvie.exception.ErrorCode;
import com.wei.youvie.model.dto.user.UserQueryRequest;
import com.wei.youvie.model.entity.User;
import com.wei.youvie.model.enums.UserRoleEnum;
import com.wei.youvie.model.vo.LoginUserVO;
import com.wei.youvie.model.vo.UserVO;
import com.wei.youvie.service.UserService;
import com.wei.youvie.mapper.UserMapper;
import lombok.extern.slf4j.Slf4j;
import org.springframework.beans.BeanUtils;
import org.springframework.stereotype.Service;
import org.springframework.util.DigestUtils;

import javax.servlet.http.HttpServletRequest;

import java.util.ArrayList;
import java.util.List;
import java.util.stream.Collectors;

import static com.wei.youvie.constant.UserConstant.USER_LOGIN_STATE;

/**
 * @author Youvie
 * @description 针对表【user(用户)】的数据库操作Service实现
 * @createDate 2025-04-01 16:58:50
 */
@Service
@Slf4j
public class UserServiceImpl extends ServiceImpl<UserMapper, User>
        implements UserService {

    /**
     * 用户注册方法
     *
     * @param userAccount   用户账号
     * @param userPassword  用户密码
     * @param checkPassword 确认密码
     * @param userName      用户名
     * @return 注册用户的ID
     * @throws BusinessException 业务异常
     */
    @Override
    public long userRegister(String userAccount, String userPassword, String checkPassword, String userName) {

        //1、 参数检查
        if (StrUtil.hasBlank(userAccount, userPassword, checkPassword)) {
            throw new BusinessException(ErrorCode.PARAMS_ERROR, "参数为空");
        }
        if (userAccount.length() < 4) {
            throw new BusinessException(ErrorCode.PARAMS_ERROR, "用户账号长度过短，必须大于3");
        }
        if (userPassword.length() < 8) {
            throw new BusinessException(ErrorCode.PARAMS_ERROR, "密码长度必须大于等于 8");
        }
        if (!userPassword.equals(checkPassword)) {
            throw new BusinessException(ErrorCode.PARAMS_ERROR, "两次输入密码不一致");
        }
        //1、 账号验重
        QueryWrapper<User> qw = new QueryWrapper<>();
        qw.eq("userAccount", userAccount);
        Long count = this.baseMapper.selectCount(qw);
        if (count > 0) {
            throw new BusinessException(ErrorCode.PARAMS_ERROR, "账号重复");
        }
        //3、添加账户
        User user = new User();
        user.setUserAccount(userAccount);
        user.setUserName(userName);
        user.setUserPassword(getEncryptPassword(userPassword));
        user.setUserRole(UserRoleEnum.USER.getValue());

        boolean saved = this.save(user);
        if (!saved) {
            throw new BusinessException(ErrorCode.SYSTEM_ERROR, "注册失败，数据库错误");
        }

        return user.getId();
    }

    /**
     * 根据用户密码获取加密后的密码。
     *
     * @param userPassword 用户输入的原始密码
     * @return 加密后的密码字符串
     */
    @Override
    public String getEncryptPassword(String userPassword) {
        // 盐值，混淆密码
        final String SALT = "youvie";
        return DigestUtils.md5DigestAsHex((SALT + userPassword).getBytes());
    }

    /**
     * 用户登录
     *
     * @param userAccount  用户账号
     * @param userPassword 用户密码
     * @param request      HttpServletRequest对象
     * @return 登录成功的用户信息
     * @throws BusinessException 业务异常
     */
    @Override
    public LoginUserVO userLogin(String userAccount, String userPassword, HttpServletRequest request) {
        // 1. 校验
        if (StrUtil.hasBlank(userAccount, userPassword)) {
            throw new BusinessException(ErrorCode.PARAMS_ERROR, "参数为空");
        }
        if (userAccount.length() < 4) {
            throw new BusinessException(ErrorCode.PARAMS_ERROR, "账号错误");
        }
        if (userPassword.length() < 8) {
            throw new BusinessException(ErrorCode.PARAMS_ERROR, "密码错误");
        }
        // 2. 加密
        String encryptPassword = getEncryptPassword(userPassword);
        // 查询用户是否存在
        QueryWrapper<User> queryWrapper = new QueryWrapper<>();
        queryWrapper.eq("userAccount", userAccount);
        queryWrapper.eq("userPassword", encryptPassword);
        User user = this.baseMapper.selectOne(queryWrapper);
        // 用户不存在
        if (user == null) {
            log.info("user login failed, userAccount cannot match userPassword");
            throw new BusinessException(ErrorCode.PARAMS_ERROR, "用户不存在或密码错误");
        }
        // 3. 记录用户的登录态
        request.getSession().setAttribute(USER_LOGIN_STATE, user);
        return this.getLoginUserVO(user);
    }


    /**
     * 获取当前登录用户信息
     *
     * @param request HttpServletRequest对象，用于从请求中获取会话信息
     * @return 返回当前登录的用户信息对象
     * @throws BusinessException 如果用户未登录，则抛出BusinessException异常
     */
    @Override
    public User getLoginUser(HttpServletRequest request) {
        // 先判断是否已登录
        Object userObj = request.getSession().getAttribute(USER_LOGIN_STATE);
        User currentUser = (User) userObj;
        if (currentUser == null || currentUser.getId() == null) {
            throw new BusinessException(ErrorCode.NOT_LOGIN_ERROR, "未登录");
        }
        return currentUser;
    }


    /**
     * 根据用户对象生成登录用户视图对象
     *
     * @param user 用户对象
     * @return 登录用户视图对象，如果输入的用户对象为null，则返回null
     */
    @Override
    public LoginUserVO getLoginUserVO(User user) {
        if (user == null) {
            return null;
        }
        LoginUserVO loginUserVO = new LoginUserVO();
        BeanUtils.copyProperties(user, loginUserVO);
        return loginUserVO;
    }

    @Override
    public boolean userLogout(HttpServletRequest request) {
        // 先判断是否已登录
        Object userObj = request.getSession().getAttribute(USER_LOGIN_STATE);
        if (userObj == null) {
            throw new BusinessException(ErrorCode.OPERATION_ERROR, "未登录");
        }
        // 移除登录态
        request.getSession().removeAttribute(USER_LOGIN_STATE);
        return true;
    }


    /**
     * 将 User 对象转换为 UserVO 对象
     *
     * @param user User 对象
     * @return 转换后的 UserVO 对象，如果传入的 user 为 null，则返回 null
     */
    @Override
    public UserVO getUserVO(User user) {
        if (user == null) {
            return null;
        }
        UserVO userVO = new UserVO();
        BeanUtils.copyProperties(user, userVO);
        return userVO;
    }

    /**
     * 根据用户列表转换为用户视图对象列表
     *
     * @param userList 用户列表
     * @return 用户视图对象列表
     */
    @Override
    public List<UserVO> getUserVOList(List<User> userList) {
        if (CollUtil.isEmpty(userList)) {
            return new ArrayList<>();
        }
        return userList.stream().map(this::getUserVO).collect(Collectors.toList());
    }

    /**
     * 根据用户查询请求生成查询条件包装器
     *
     * @param userQueryRequest 用户查询请求对象
     * @return 查询条件包装器
     * @throws BusinessException 请求参数为空时抛出业务异常
     */
    @Override
    public QueryWrapper<User> getQueryWrapper(UserQueryRequest userQueryRequest) {
        if (userQueryRequest == null) {
            throw new BusinessException(ErrorCode.PARAMS_ERROR, "请求参数为空");
        }
        Long id = userQueryRequest.getId();
        String userAccount = userQueryRequest.getUserAccount();
        String userName = userQueryRequest.getUserName();
        String userRole = userQueryRequest.getUserRole();
        String userProfile = userQueryRequest.getUserProfile();
        String sortField = userQueryRequest.getSortField();
        String sortOrder = userQueryRequest.getSortOrder();

        QueryWrapper<User> queryWrapper = new QueryWrapper<>();
        queryWrapper.eq(id != null, "id", id)
                .like(StrUtil.isNotBlank(userAccount), "userAccount", userAccount)
                .like(StrUtil.isNotBlank(userName), "userName", userName)
                .eq(StrUtil.isNotBlank(userRole), "userRole", userRole)
                .like(StrUtil.isNotBlank(userProfile), "userProfile", userProfile)
                .orderBy(StrUtil.isNotBlank(sortField), sortOrder.equals("ascend"), sortField);
        return queryWrapper;
    }

    /**
     * 判断用户是否为管理员
     *
     * @param user 用户对象
     * @return 如果用户是管理员，则返回true；否则返回false
     */
    @Override
    public boolean isAdmin(User user) {
        return user != null && UserRoleEnum.ADMIN.getValue().equals(user.getUserRole());
    }

}


